The rocker-type electrical wall switch has long been known for its advantages of operating switch contacts through limited angular movement of a pivoted rocker, thus allowing the ends of the rocker to remain substantially flush in the rocker frame for aesthetics. U.S. Pat. No. 3,770,920 to Polliak disclosed a rocker-type switch in which the rocker is pivotally supported in a housing at a first pivot point, a movable plate supporting a contact brush is pivotally supported at a second pivot point in the housing, and a spring is compressed between a downwardly extending boss on the rocker and a lower end of the plate supporting the contact brush, so that the spring is movable under compression to bias the contact brush plate to opposite inclined positions in response to pivotal movement of the rocker between its up and down positions. The contact brush makes contact in each rocker position with a switch contact supported on a respective one of a pair of terminal plates to which respective wire leads are attached, in order to form a single-pole rocker-type switch.
U.S. Pat. No. 5,382,768 to Kurek et al. disclosed another rocker-type switch in which a rocker actuator arm is moved in response to movement of a rocker cover to move a slider back and forth to open and close one or more pairs of switch contacts. Rocker movement is controlled by a rocker cam leaf spring which has a cammed profile traversed by the rocker cam to move the slider between switch contact positions, lock the rocker and provide other desired functions. The rocker cam spring is housed in a spring chamber longer than itself, allowing the rocker cam spring to float. A fixed terminal assembly is engaged with a switch contact assembly against which the slider moves to make contact and thereby close the switch, or moves away from to open the switch. The terminal assembly can be implemented in single-pole, double-pole, and double-throw for 3-wire or 4-wire circuit arrangements. A sheet metal mounting strap provides a cradle-like support for holding the switch in a wall box.
U.S. Pat. No. 5,950,812 to Tanacan et al. disclosed another rocker-type switch in which a star-shaped spring provides the necessary forces to hold the rocker to a switch spacer and to couple the rocker to a movable contact arm. The movable contact arm is inserted in the switch spacer and makes contact between opposing switch contacts. The star-shaped spring is made of flat spring stock and is selectively bent with star-shaped bends to enable the various switch contact functions. A V-notch receives the end of the movable contact arm and moves the arm between the two switch contact positions as the rocker is operated.
While there have been many variations of and improvements to the rocker-type switch, the conventional rocker-type switch still has certain problems that remain to be solved. One main problem is that changing the arrangement of the rocker-type switch to single-pole, double-pole, 3-way, or 4-way switch configurations requires that different terminal plates or wiring arrangements be used with different insulative parts in the terminal housing subassembly, thereby requiring substantial change to or reconfiguration of the switch parts. Also, the manufacture of different insulative parts of expensive, high temperature plastic material increases the costs for the overall product line. The required assembly of different manufactured parts in different configurations also results in tolerance error stack-up when the parts are assembled together, thereby leading to problems in terms of fit and alignment of the parts and the switch contacts.